The days are getting shorter. The sunlight is getting dimmer. And, my eyes are getting weaker. So, I did what nearly no-one else would: I built a power supply and some light panels.
I had a few LED strips left over from project lightboard. These ones were aluminum-backed with a diffuser, and, are 5000K. They are nominally 12V, so first was to connect it to the bench power supply (a BAKU BK-305D). This power supply is, well, it is what it is. Its relatively cheap, its relatively accurate. And, its linear. So, the efficiency is imperfect. It operates by selecting multiple taps fro ma transformer, as your voltage goes up, it switches to the next tap perioidcally so the drop across the output transistors is not too high. Previouly I added a thermostatic fan to it. Nonetheless, its too loud for the lights. Prototype achieved, but, next.
OK, I have a DPS3005. These can be had pretty cheaply and, are quite excellent. They are a buck-converter with a small OLED display, allowing constant-voltage, constant-current, and simple metering. I also have (more than one) old laptop power supply, these are typically 20V. I chose a lenovo one with 65W @ 20V, should be lots.
A quick trip through the 3D printer yielded this case. A bit of soldering, some banana jacks, I chose a XT60 connector for the input (since the Lenovo had a rectangular I dunno what type connector).
OK, installed, a bit of hot melt glue in the usual spots, and, put it in its final place. Now we have a very complex dimmer, and, light.
You are probably asking about the IBM PC jr button. Yeah, I’ve had that for a few years, I got it new back in the day. I’ll let you lookup what day that was.
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